Cisplatin induced apoptosis of ovarian cancer A2780s cells by activation of ERK/p53/PUMA signals
Hao Song1, Mei Wei2, Wenfen Liu3, Shulin Shen3, Jiaqun Li4 and Liming Wang5
1Department of Radiotherapy, 2Department of Surgery, The Affiliated Hospital of Qingdao University, Qingdao, 3Department of Gynaecology, 4Department of Clinical Laboratory, People's Hospital of Weifang, Weifang and 5Department of Gynaecology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
Offprint requests to: Liming Wang, Department of Gynaecology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China. e-mail: gjzgk321@126.com and wlmqingyi@163.com
Summary. Cisplatin (CDDP) is one of the most effective anticancer agents widely used in the treatment of solid tumors, including ovarian cancer. It is generally considered as a cytotoxic drug which kills cancer cells by causing DNA damage, and subsequently inducing apoptosis in cancer cells. However, the underlying mechanisms leading to cell apoptosis remain obscure. In this study, the signaling pathways involved in CDDP -induced apoptosis were examined using CDDP-sensitive ovarian cancer A2780s cells. A2780s cells were treated with CDDP (1.5-3 μg/ml) for 6 h,12 h and 24 h. Using siRNA targeting P53 and PUMA, and a selective MEK inhibitor, PD98059 to examine the relation between ERK1/2 activation, p53 and PUMA expression after exposure to CDDP, and the effect on CDDP-induced apoptosis. The results shown that treatment of A2780s cells with CDDP (3 μg/ml) for 6-24h induced apoptosis, resulting in the activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and accumulation of p53 and PUMA (p53 upregulated modulator of apoptosis) protein. Knockdown of P53 or PUMA by siRNA transfection blocked CDDP-induced apoptosis. Inhibition of ERK1/2 using PD98059, a selective MEK inhibitor, blocked the apoptotic cell death but prevented CDDP-induced accumulation of p53 and PUMA. Knockdown of P53 by siRNA transfection also blocked CDDP-induced accumulation of PUMA. We therefore concluded that CDDP activated ERK1/2 and induced-p53-dependent PUMA upregulation, resulting in triggering apoptosis in A2780s cells. Our study clearly demonstrates that the ERK1/2/p53/PUMA axis is related to CDDP-induced cell death in A2780s cells. Histol Histopathol 33, 73-79 (2018)
Key words: Ovarian cancer, Cisplatin, Apoptosis, ERK1/2, P53, p53 upregulated modulator of apoptosis
DOI: 10.14670/HH-11-889